1. Field of the Invention
The present invention relates to a method and an arrangement for manufacturing rolled wire or round steel sections in coils from carbon steels or high-grade steels. In the method and arrangement, billets are used as the initial material. The billets are removed at rolling temperature from a billet furnace and, in successive steps of operation, are rolled in a multiple-stand rolling mill train into wire sections or round steel sections, hexagonal steel sections or square steel sections and, in a sequence of aftertreatment steps, the wire sections or round steel sections are wound into coils, are cooled and transferred to a coil conveyor, wherein these aftertreatment steps are carried out in accordance with material quality and/or predetermined end product quality in different stations, and particularly with different temperature gradients.
2. Description of the Related Art
The above-described method and arrangement are used particularly in the manufacture of different steel qualities, preferably of alloy qualities-for example, high-grade steels. The steels are cooled as required slowly, with a delay, or quickly. The method and the arrangement are particularly suitable for the production of wire products having diameters of 5 to 20 mm and for round steel dimensions of 10 to 60 mm.
The following methods of aftertreatment in a wire production line are known in the art:
a) Cooling with air, for example, Stelmor method; PA1 b) delayed cooling without air, for example, Stelmor method with insulation chambers; PA1 c) slow cooling, for example, in insulation hoods or insulation chambers which are also heatable; PA1 d) quick cooling, for example, in a water bath. PA1 e) quick cooling, for example, in a water Garrett reel; PA1 f) delayed cooling, for example, in a Garrett reel with subsequent transport through an insulation chamber; PA1 g) slow cooling, for example, in a Garrett reel with subsequent transport through an insulation chamber which is also heatable, or with insulation hoods being placed over the coils, to storage locations. PA1 a) a wire production line with a multiple-stand wire mill and a round steel production line with, for example, a multiple-stand round steel mill which branches from a common billet supply line including a billet furnace and a cooling bed, wherein the wire mill and the round steel mill are arranged next to each other; PA1 b) an aftertreatment unit following the production lines including:
Round steel production lines in coils conventionally include the following aftertreatment methods:
In the past, each production line for wire or round steel was followed by a separate aftertreatment plant. In the manufacture of wire and round steel sections with frequently changing steel qualities, for example, carbon steels and/or high-grade steels with different quality features and, thus, different thermal aftertreatments or final treatments (particularly in comparatively small batches, such an arrangement of the production lines with substantial separate aftertreatment units results in relatively high investment and operation costs). As a result, the price of the products is increased in an uneconomical manner.